2011/11/22 by Ariadna Blanca-Romero, Ariadna Blanca‐Romero, Rossitza Pentcheva · 3 citations
Chemistry · Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Atomic physics #Chemistry #Condensed matter physics #Crystallography #Density functional theory #Dielectric #Disproportionation #Electronic and Structural Properties of Oxides #Ferroelectricity #Ground state #Lanio #Magnetic and transport properties of perovskites and related materials #Materials science #Physics #cond-mat.mtrl-sci #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.84.195450
published as Physical Review B 84, 195450 (2011) · 7 pages, 10 Figures
openalex publication_date 2011/11/22 · arxiv created 2012/08/15 · arxiv updated 2012/08/16 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Using density functional theory calculations including a Hubbard U term we explore the effect of strain and confinement on the electronic ground state of superlattices containing the band insulator LaAlO3 and the correlated metal LaNiO3. Besides a suppression of holes at the apical oxygen, a central feature is the asymmetric response to strain in single unit cell superlattices: For tensile strain a band gap opens due to charge disproportionation at the Ni sites with two distinct magnetic moments of 1.45\ensuremathμB and 0.71\ensuremathμB. Under compressive stain, charge disproportionation is nearly quenched and the band gap collapses due to overlap of d_3z2\ensuremath-r2 bands through a semimetallic state. This asymmetry in the electronic behavior is associated with the difference in octahedral distortions and rotations under tensile and compressive strain. The ligand hole density and the metallic state are quickly restored with increasing thickness of the (LaAlO3)n/(LaNiO3)n superlattice from n=1 to n=3.